I always did think that there might be something that happens in this film that will cause Thor to leave Asgard by the end of the film and stay on Earth which would allow him to become more established as a hero on Earth to its inhabitants and that we wouldn't have to wait to see Thor appear on screen once the Avengers 2 came out.

That is another excellent point. This scenario might allow him to do that in a way that makes sense.

and not to make it about Loki (as some of you know I often do ) but....

Spoiler!!! Click to Read!:

wouldn't it be a major surprising twist if in the process of all of this, Thor loses favor with Odin, and Loki on the other hand stays and fights for Asgard and gains Odin's favor and approval finally?